/Engine/Source/Runtime/MeshDescription/Public/MeshAttributeArray.h
This is the container for all attributes and their arrays. It wraps aTMap, mapping from attribute name to attribute array. An attribute may be of any arbitrary type; we use a mixture of polymorphism and compile-time templates to handle the different types.
class FAttributesSetBase
TMap<FName,FA...
Map
The actual container
int32
NumElements
The number of elements in each attribute array